I do not, and never will keep to canon. Don't like it, go cry in a corner.

Fandoms:

Sonic - Admittedly I center this mostly on the KTE Archie universe, but I like all the main stuff too.
Harry Potter - I'm not a big fan of the slash in this one, except for a very crack couple _
Ouran High School Host Club - I like all pairings, though there should be more of Morinozuka. I mean really.
Jigoku Shoujo - I'd be quite pissed off if I read something which ever put Ai out of character.
Deathnote - Main slash wahey.
School Rumble - Funny flat chested dumbasses are funny.
Fullmetal Alchemist - I love, freakin love this show.
Avatar, legend of Aang - WONDERFUL

and moarrrrrr.

What I like:

Well written lemons, so fuckin rare.
Non clichenessss, especially in romance.
Good angst, honestly a cry never felt so good.
Good characterization
Imagery. Nom.
Sexual tension. Because you don't go vagina dipping without some awkwardness!

Sonic couples I like, because there are just too many:

SonicAmy - if written well. Lets face it, Sonic won't propose to Amy unless she quits stalking.
ShadowAmy - because angst never looked so good.
KnucklesAmy - honestly, I think they'd be good together
SonicShadow - nothin' like some cliche main character slash!
KnucklesShadow - simply nom.
KnucklesSonic - because differences are hawt.
JulieKnuckles - they suit each other really sexily - I mean, well
RougeKnuckles - if served up well
ShadowJulie - because, honestly, a brilliant story made me love them
ShadowRouge - its alllll guuuuddddd
LockeLara - ffffffff gimme

now for the crack

SpectreDimitri
LockeJulie
JulieBrotherhood (oh god XD)
andd well. cest.

wahaha!